The present invention relates to a high pressure plunger pump. More particularly, it relates to a high pressure plunger pump with a centrally arranged pressure valve, a plunger movable by an oscillating drive and limiting a working chamber, a sleeve which is exclusively guided by the plunger and surrounded by a suction chamber accommodating the aspirating fluid.
High pressure plunger pumps of the above-mentioned general type are known in the art. In a known high pressure plunger pump, the sealing between the plunger and the sleeve which is floatingly supported on it is performed exclusively by the gap between both above-mentioned parts. This gap sealing is sufficient within a wide pressure region. However, with a working pressure which is greater than 2,000 bar, a loss of half displacement output occurs with the exclusive use of the gap sealing between the plunger and the sleeve arranged on it.